LARIMER COUNTY, Colo. (CBS4) – Larimer County Sheriff Justin Smith sent a letter to his department in reaction to the murder of two police officers in New York City.

Ismaaiyl Brinsley ambushed and killed two NYPD officers in Brooklyn Saturday. He reportedly began his day by shooting his ex-girlfriend and making online posts that were “very anti-police,” Police Commissioner Bill Bratton said.

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“Like all of you, I grieve the loss and at the same time I am outraged by this heinous, murderous act,” Smith said in his letter that he also posted on Twitter.

Smith believes a “small group of committed societal agitators works endlessly behind the scenes to sow seeds of distrust and hatred between communities and their police officers.”

“Their ultimate goal is to break down the bonds that hold us together as Americans and to destroy the rule of law as we know it. Oftentimes, they do this under the mantra of promoting social justice,” Smith said.

He said those people are trying to convince Americans that the police are their enemies.

“Yesterday’s murder of these two officers represents a symbol of their success,” Smith said. “However, it’s critical to this group that these events result in police officers, in turn, adopting an adversarial attitude towards the communities they serve.”

He continues to tell his department to “commit to keeping our communities, our brother and sister officers and ourselves safe, while continuing to be the public servants that we committed to be when we raised our right hands and took the oath of office.”